No offense but I'm more inclined to believe that KIA stepped in themselves to handle the problem rather than NAZA, which is still good because they pay attention to customer needs.

Peugeot is handled by Nasim which is also part of Naza but look at the number complaints they have, very unbecoming for a European marque.

So good job KIA.

I don't know if this is applicable for the K5 but the air recirculation is suppose to shut itself off on start up. For all Euro cars, including Mercedes Benz etc, it will shut off after awhile to let fresh air in if the air recirculation has been switched on. Upon engine startup, the air recirculation system is OFF by default as well even if it was switched on when you engine off the car.

http://www.euro-gasman.com/PDFs/C2%20Examp...s%20Testing.pdf

They have some safety law in Euro that states the amount of CO2 present in an enclosed space cannot exceed a certain amount for a certain period of time. Seeing that the newer KIAs are all designed and have European designers, they may have adopted the same system.

It LOOKS like the K5 air conditioning system also has a CO2 sensor like a lot of the European cars to comply to this safety law.

Maybe replace the cabin or air cond filters. If that don't work, means you have to get the SC to flush the HVAC system clean.